/*	$NetBSD: strchkread.c,v 1.3 2003/08/07 10:30:50 agc Exp $
 *
 * Copyright (c) 1986, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *	@(#)strchkread.c	8.1 (Berkeley) 6/8/93
 */
#include <arpa/inet.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <netinet/in.h>
#include <netdb.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#define TRUE 1

/*
 * This program uses select() to check that someone is trying to connect
 * before calling accept().
 */

int main()
{
	int sock;
	socklen_t length;
	struct sockaddr_in server;
	int msgsock;
	char buf[BUFSIZ];
	int rval;
	fd_set ready;
	struct timeval to;
	struct sockaddr_in client;
	char *client_addr;

	/* Create socket */
	sock = socket(AF_INET, SOCK_STREAM, 0);
	if (sock < 0) {
		perror("opening stream socket");
		exit(1);
	}

	/* Name socket using wildcards */
	server.sin_family = AF_INET;
	server.sin_addr.s_addr = INADDR_ANY;
	server.sin_port = 0;
	if (bind(sock, (struct sockaddr *)&server, sizeof(server)) != 0) {
		perror("binding stream socket");
		exit(1);
	}

	/* Find out assigned port number and print it out */
	length = sizeof(server);
	if (getsockname(sock, (struct sockaddr *)&server, &length) != 0) {
		perror("getting socket name");
		exit(1);
	}
	printf("Socket has port #%d\n", ntohs(server.sin_port));

	/* Start accepting connections */
	listen(sock, 5);
	do {
		FD_ZERO(&ready);
		FD_SET(sock, &ready);
		to.tv_sec = 5;
		to.tv_usec = 0;
		if (select(sock + 1, &ready, 0, 0, &to) < 0) {
			perror("select");
			continue;
		}
		if (FD_ISSET(sock, &ready)) {
			length = sizeof(client);
			msgsock = accept(sock, (struct sockaddr *)&client, &length);
			client_addr = inet_ntoa(client.sin_addr);
			printf("Client connection from %s!\n", client_addr);
			if (msgsock == -1)
				perror("accept");
			else do {
				bzero(buf, sizeof(buf));
				if ((rval = read(msgsock, buf, BUFSIZ)) < 0)
					perror("reading stream message");
				else if (rval == 0)
					printf("Ending connection from %s.\n", client_addr);
				else
					printf("Client (%s) sent: %s", client_addr, buf);
			} while (rval > 0);
			close(msgsock);
		} else
			printf("Do something else\n");
	} while (TRUE);
	return 0;
}
